feat: client credential flow for actions oauth

[peeeteeer]

Pull Request Template

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Summary

The Change enables the OAuth Authentication Feature to also work with Client Credential Flow which is used often by large enterprises to secure APIs.

Change Type

Please delete any irrelevant options.

• New feature (non-breaking change which adds functionality)

Testing

Please describe your test process and include instructions so that we can reproduce your test. If there are any important variables for your testing configuration, list them here.

• Tested locally and in our production environment deployed as docker containers
• Tested both flows are working
• Tested persistence of new field is correct

Checklist

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• [x ] My code adheres to this project's style guidelines
• I have performed a self-review of my own code
• [x ] My changes do not introduce new warnings

Peter Rothlaender [email protected] on behalf of Daimler Truck AG.
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